RU2795662C1 - Device for pressure testing of double-row preventer for a well - Google Patents

Abstract

FIELD: oil industry.

SUBSTANCE: invention is related to devices for pressure testing a double-row preventer in a well. The two-row preventer pressure device for a well includes a preventer body with pipe rams installed in it, forming a hole for the support pipe. The support pipe is passed through the body of the preventer and has the possibility of external sealing with pipe rams of the preventer. The device also contains a packer installed in the well, and a pump for filling the well with liquid and pressurizing the preventer. The preventer is made with double rows, the hole formed by the lower row pipe rams is displaced relative to the hole formed by the upper row pipe rams, which ensures successive pressure testing of the pipe rams. The device is equipped with two sealed support tubes, and the holes formed when the pipe slips of the lower and upper rows are closed are located opposite the support pipes with the possibility of their airtight coverage. From below, the support pipes are plugged and passed through the axial channel of the preventer. Couplings are screwed onto the upper end of the support pipes, allowing the support pipes to be suspended sequentially on the elevator. The packer is made retrievable with a hydraulic seat, the pump is hydraulically connected to the annulus of the well. For installation and dismantling of the device, a lifting structure with slings is used.

EFFECT: functionality of the device is expanded, the reliability of the device in operation is increased, the labor intensity of work on pressure testing of a preventer with two rows of rams is reduced, and the quality of pressure testing of pipe rams of a preventer is also improved.

1 cl, 3 dwg

Description

The invention relates to the oil industry, in particular to devices for pressure testing a double-row preventer in a well.

A well-known stand for pressure testing of a preventer in a well (patent RU 2719879, IPC E21V 33/03, publ. 04/23/2020), including a support pipe passing through the preventer body, a hollow rod installed in the support pipe and a packer in the form of a rubber cuff placed on the support pipe , the outer surface of the support pipe is equipped with a closed curly groove, and above the closed curly groove it is equipped with a stepped annular selection, consisting of lower and upper steps, and the curly groove consists of longitudinal short and long sections, while opposite the curly groove on the outer surface of the support pipe, movably placed a spring-loaded collet with a guide pin placed in a shaped groove, while the longitudinal short and long sections of the shaped groove are connected to each other by a closed figured section so that during axial reciprocating movement of the collet relative to the support tube, the guide pin will be located in the longitudinal short section of the figured groove groove - the transport position in which the collet interacts with the lower step of the outer stepped annular selection of the support pipe, then in the longitudinal long section of the figured groove - the working position in which the collet interacts with the upper step of the outer stepped annular selection of the support pipe, and the lower part of the rubber cuff, made in the form of a hollow cylinder, rigidly fixed on the lower part of the support pipe, while the upper part of the rubber cuff is put on the mandrel, rigidly fixed on the support pipe, while above the mandrel, but below the shaped groove, the support pipe is equipped with a number of radial holes, and opposite the mandrel is equipped with through longitudinal grooves, in which movable fingers are installed, which are connected to the mandrel on one side, and on the other side are connected to a hollow rod, which is equipped with a check valve from above and spring-loaded from the support pipe from below, and in the transport position the hollow rod hermetically covers a number of radial openings of the support pipe, while from below the hollow rod hydraulically communicates the spaces above and below the support pipe, and in the working position, the hollow rod has the possibility of axial limited movement down within the through longitudinal grooves of the support pipe until a number of radial holes in the support pipe open, and the support pipe is below the rubber the cuff is equipped with a spring centralizer, and the outer diameter d1 of the spring centralizer is greater than the outer diameter d2 of the rubber cuff in the transport position, while the upper end of the support pipe is hydraulically connected to the pump.

The disadvantages of the stand are:

- firstly, the limited functionality of the stand, which consists in the fact that the stand is not intended for pressure testing of a preventer with two rows of rams (upper and lower) located eccentrically;

- secondly, low reliability of operation, due to the high probability of loss of the stand tightness during pressure testing, since after each pressure test of the preventer ram, it is necessary to unpack the packer, lift it to the wellhead with the support pipe, change the standard size of the support pipe for the preventer ram being pressed, lower the packer again on the support pipe and set the packer. Such work is repeated more than once, depending on the size of the support pipe sealed by the preventer and the rams under them, which will ultimately lead to loss of tightness and failure of the bench in operation;

- thirdly, high labor intensity and cost of use, since the device is disposable, i.e. after each pressurization of the preventer, it is necessary to disassemble it, revise it, change the size of the slips for the sealed support pipe, reassemble and set the packer, which increases the cost of the stand maintenance;

- fourthly, the poor quality of pressure testing of the pipe rams of the preventer, due to the lack of precise centering of the axis of the support pipe and the axis of the interlocking rams. As a result, it is possible to obtain a loss of tightness of the pressure test due to a violation of the alignment of the support pipe relative to the axis of the well, and as a result, poor quality pressure test of the pipe rams of the preventer;

- fifthly, low efficiency in operation, associated with a low probability of fixing the packer collet in the gap of the pipe coupling even under the condition: a < b,

where a is the height of the fixing part of the collet,

b - coupling gap height.

In practice, asphaltene-paraffin deposits are present on the inner walls of the wells, which will not allow the collet to be fixed in the gap of the well casing collar.

Closest to the proposed is a device for pressure preventer, including the body of the preventer with a pipe ram installed in it, forming a hole for the support pipe, the support pipe is passed through the body of the preventer and has the possibility of external sealing with pipe rams of the preventer, a packer installed in the well, a pump for filling the well liquid and pressuring the preventer (patent RU 2708748, IPC E21B 33/03, publ. 12/11/2019). The packer consists of lower and upper rubber cuffs with a washer between them. An external cylindrical recess is made on the support pipe, in which a support plate is installed from the bottom up, made from below under a cone, tapering from top to bottom, and from above the support plate is made under an inverse cone, tapering from bottom to top, a lower rubber collar, a washer, an upper rubber collar and a clamping plate , while the inner diameter of the lower rubber cuff is larger than the inner diameter of the upper rubber cuff, and in the transport position, the reverse cone of the support plate interacts from above with the lower rubber cuff, and the upper ends of the support and clamping plates interact with the ends of the outer cylindrical sample, and in the support pipe opposite the clamping plate, a vertical through groove is made in which a pin is installed, while the pin is rigidly fixed on one side in the clamping plate, and on the other side in the hollow stem with the possibility of limited movement within the vertical through groove in the working position, while the hollow stem is equipped with a seat from below a saddle for a locking element dropped into the pipe, moreover, the support and clamping plates are equipped with conical chamfers for rubber cuffs, which prevent the rubber cuffs from leaking behind the support and clamping plates when they are sealed in the well, while the support pipe below the support plate is equipped with a mechanical anchor with a guide pin, placed in a shaped groove, made on the outer surface of the support pipe in the form of interconnected horizontal and vertical grooves, while the mechanical anchor has the ability to move radially and axially within the shaped groove, while the upper end of the support pipe and the annulus of the well are hydraulically connected to the pump .

The disadvantages of the device are:

- firstly, the limited functionality of the device, which consists in the fact that the device is not intended for pressure testing of a preventer with two rows of rams (upper and lower) located eccentrically;

- secondly, low reliability of operation, due to the high probability of loss of tightness of the device during pressure testing, since after each pressure test of the preventer ram, it is necessary to unpack the packer, raise it to the wellhead with a support pipe, change the standard size of the support pipe for the preventer ram being pressed, lower the packer again on the support pipe and set the packer. Such work is repeated more than once, depending on the size of the support pipe sealed by the preventer and the rams under them, which will ultimately lead to loss of tightness and failure of the device in operation;

- thirdly, high labor intensity and cost of use, since the device is disposable, i.e. after each pressurization of the preventer, it is necessary to disassemble it, revise it, change the size of the slips for the sealed support pipe, reassemble and set the packer, which increases the cost of maintaining the device;

- fourthly, the poor quality of pressure testing of the pipe rams of the preventer, due to the lack of precise centering of the axis of the support pipe and the axis of the interlocking rams. As a result, it is possible to obtain a loss of tightness of the pressure test due to a violation of the alignment of the support pipe relative to the axis of the well, and as a result, poor-quality pressure testing of the pipe rams of the preventer.

The technical results of the invention are to expand the functionality of the device, increase the reliability of the device in operation, reduce the labor intensity and cost of carrying out pressure testing of a preventer with two rows of rams, as well as improve the quality of pressure testing of pipe rams of the preventer.

The technical results are achieved by a device for pressure testing a double-row preventer in a well, including a preventer body with pipe rams installed in it, forming a hole for a support pipe, a support pipe is passed through the preventer body and has the possibility of external sealing with preventer pipe rams, a packer installed in the well, a pump for filling the well with liquid and pressure testing the preventer.

What is new is that the preventer is made in two rows, the hole formed by the lower row pipe rams is offset relative to the hole formed by the upper row pipe rams, which ensures sequential pipe ram crimping, the device is equipped with two sealed support pipes, and the holes formed by closing the lower row pipe rams and the upper rows, located opposite the support pipes with the possibility of their tight coverage, and from below the support pipes are plugged and passed through the axial channel of the preventer, and couplings are screwed onto the upper end of the support pipes, which allow the support pipes to be sequentially suspended on the elevator, the packer is made retrievable with a hydraulic landing, at the same time, the pump is hydraulically connected to the annulus of the well, while a lifting structure with slings is used to mount and dismantle the device.

In FIG. 1 schematically shows a device for pressure testing a double-row preventer on a well in its initial position.

In FIG. 2 schematically shows a device for pressure testing a double-row preventer in a well in the working position during pressure testing of the lower row of tubular rams of a double-row preventer.

In FIG. 3 schematically shows a device for pressure testing a double-row preventer in a well in the working position during pressure testing of the upper row of tubular rams of a double-row preventer.

The double-row preventer is designed to ensure the safety of maintenance personnel at the wellhead when working with a two-lift pipe string equipped inside with downhole equipment in case of blowouts at the wellhead in the form of oil and gas water shows (OGWP). The safety requirement is the mandatory installation of blowout prevention equipment (BOP) at the wellhead of the production well (simultaneously separate operation of the well in two pipe strings) and the injection well (simultaneously separate injection). At the same time, various combinations of standard sizes of tubing (tubing) according to GOST 633-80 are lowered into a production or injection well, namely, with outer diameters:

48mm×48mm

48mm×60mm

60 mm × 60 mm.

The proposed device is necessary to check the tightness of the dies designed to seal each pipe in any of these combinations. And it is necessary to exclude leakage of the rams during tripping operations on the well in the event of an OGWP in order to ensure the safety (life and health) of the maintenance personnel working at the mouth of a production or injection well.

Device for pressure testing double-row preventer 1 on the well (Fig. 1, 2 and 3) includes a preventer housing 2, which houses the lower row of 3 tubular rams and the upper row 4 of tubular rams.

Hole 5 (Fig. 1), formed by the tube rams of the upper row 4, is offset relative to the hole 6 (Fig. 1), formed by the tube rams of the lower row 3.

The device is equipped with two sealed support pipes 7 (Fig. 2) and 8 (Fig. 3). Support pipes 7 and 8 are designed for successive testing of tightness, respectively, of the lower row 3 of tubular rams and the upper row 4 of tubular rams of a double-row preventer 1, by creating excess pressure (pressure testing) in well 9 (Fig. 1-3) under the preventer 1.

From below, the corresponding plugs 10 (Fig. 2) and 11 (Fig. 3) are screwed into the support pipes 7 and 8, respectively.

The packer 12 (FIGS. 1-3) is retrievable and is hydraulically set in the well 9 before the preventer is pressure tested. As a retrievable packer, any known retrievable packer plug (IPP) is used, for example, with a hydraulic landing manufactured by Neftyanik LLC (Russian Federation, Republic of Tatarstan, Bugulma). The packer 12 has at its upper end a cylindrical rod with a conical grip (not shown in FIGS. 1-3).

The pump 13 (Fig. 1-3) is hydraulically connected to the annulus 14 of the well 9. As the pump 13, a pump of any known design can be used, designed to pump fluid into the well, for example, a cementing unit of the TsA-320 brand, manufactured by Izhneftegaz LLC ( Russian Federation, Republic of Udmurtia, Izhevsk).

For installation and dismantling of the device, a lifting mast is used (not shown in the figure), for example, APRS 40.

The device works as follows.

Before installing the preventer 1 and pressure testing of pipe rams 4 and 5, the device is mounted.

In the well 9 (figure 1) using a lifting mast (not shown in the figure) on the technological pipe string (not shown in Fig. 1-3), for example, a tubing string with an outer diameter of 73 mm according to GOST 633-80 is produced descent and landing of the plug 12, which is retrievable by the packer, for example, at a depth of 50-100 m. The landing is carried out hydraulically (not shown in Fig. 1-3) using the pump 13, after landing, the technological pipe string is removed from the well 9.

Next, using a lifting mast (not shown in Fig. 1-3), a two-row preventer 1 is installed on the support flange 15 (Fig. 1-3) of the well 9, after having previously installed the sealing ring 16 (Fig. 1-3) between the lower flange of the double-row preventer 1 and the support flange 15 of the well. A double-row preventer 1 is fixed to the support flange 15 of the well 9 using studs and nuts (in Fig. 1-3 it is shown conditionally).

To crimp the pipe dies of the lower row 3 (Fig. 2) of the double-row preventer 1, a plug 10 is screwed onto the nipple end of the support pipe 7, for example, a tubing with an outer diameter of 60 mm according to GOST 633-80 (see Fig. 2).

The support pipe 7 is lowered through the axial channel 17 (Fig. 1-3) of the double-row preventer 1 into the well 9. Then the support pipe 7 is suspended on the elevator 18 (Fig. 2, 3) having previously screwed the sleeve 19 (Fig. 2) onto the upper end of the support pipes 7.

Tie the first lateral outlet 20 (Fig. 2, 3) of the well 1 with the pump unit 13 and fill the well 1 with process fluid, for example, fresh water with a density of 1000 kg/m ³ , using the pump unit 13 until the liquid is poured out through the second side outlet 21 ( Fig. 2, 3), after which the valve 22 is closed on the second side branch 21.

The well 1 is topped up with the help of the pumping unit 13 until the liquid is poured out through the axial channel 17 of the double-row preventer 1. liquid pressure under the double-row preventer to the target pressing pressure of the double-row preventer, for example, 21.0 MPa and close the valve 25 (Fig. 2, 3) of the first side outlet 20. The double-row preventer 1 is kept under the above pressure, for example, for 30 minutes, and the fall pressure of more than 5% is not allowed, i.e. after the pressure test is completed, the overpressure must be at least 19.95 MPa. Thus, the lower row of dies 3 of the double-row preventer 1 is pressure tested.

After the pressure testing of the lower row of rams 3 of the double-row preventer 1 is completed, the pressure is released by opening the valve 22 on the second side outlet 21. By rotating the handwheels 23 and 24 of the double-row preventer 1, the sealed support pipe 7 is released and the support pipe 7 with the plug 10 is removed through the axial channel 17 of the double-row preventer 1 from well 9.

Further, to crimp the pipe dies of the upper row 4 (Fig. 3) of the double-row preventer 1, a plug 11 is screwed on from below to the nipple end of the support pipe 8, for example, a tubing with an outer diameter of 48 mm according to GOST 633-80 (see Fig. 3).

The support pipe 8 is lowered through the axial channel 17 of the double-row preventer 1 with the upper row of pipe rams 4 into the well 9. Then the support pipe 8 is suspended on the elevator 18, having previously screwed the sleeve 26 (Fig. 3) onto the upper end of the support pipe 8.

The well 1 is topped up with the help of the pump unit 13 until the liquid is poured out through the axial channel 17 of the double-row preventer 1. liquid pressure under the double-row preventer to the target pressure of the preventer, for example, 21.0 MPa and close the valve 25 of the first side outlet 20. The double-row preventer 1 is kept under the above pressure, for example, for 30 minutes, and the pressure drop by more than 5% is not allowed , i.e. after the pressure test is completed, the overpressure must be at least 19.95 MPa. Thus, the upper row of dies 4 of the double-row preventer 1 is pressure tested.

After pressure testing of the upper row of rams 4 of the double-row preventer 1 is completed, pressure is released by opening the valve 22 on the second side outlet 21. By rotating the handwheels 27 and 28 of the preventer 1, the sealed support pipe 8 is released and through the axial channel 17 of the double-row preventer 1 is lifted out of the well 9. The double-row preventer is dismantled 1.

The descent of the fishing tool (not shown in Fig. 1-3), for example, the packer 12 is removed with an external pipe, the packer rod 12 is caught by the conical grip. With the help of a lifting mast, the spear is pulled up, the packer 12 is torn off from the landing site and removed from the well.

The functionality of the device is expanded, consisting in the fact that the device is designed for pressure testing of a preventer with two rows of rams (upper and lower) located eccentrically.

Reliability of work increases, losses of tightness of the device in the course of crimping are excluded. Since in this case a retrievable plug packer is used, which is planted only once and removed from the well by a fishing tool (pipe) at the end of the pressure test cycle of all pipe rams of various sizes.

The labor intensity and cost of using the device is reduced, since it is reusable and allows the pressure testing of pipe dies with a diameter of 48 and 60 mm, as well as their combination. In addition, there is no need to reassemble and set the packer after each pressure test of the preventer.

The quality of pressure testing of tubular rams of a double-row preventer is improved due to the design of the tubular rams of the upper and lower rows of the preventer, which allows precise alignment of the axes of the support pipes and the axes of the corresponding interlocking rams.

A device for pressure testing a double-row preventer in a well allows:

- expand the functionality of the device;

- improve the reliability of the device;

- reduce the complexity and cost of using the device;

- to improve the quality of pressure testing of pipe rams of the preventer.

Claims (1)

A device for pressurizing a double-row preventer in a well, including a preventer body with tubular rams installed in it, forming a hole for the support pipe, the support pipe is passed through the preventer body and has the possibility of external sealing with preventer tubular rams, a packer installed in the well, a pump for filling the well with liquid and pressurization of the preventer, characterized in that the preventer is made in two rows, the hole formed by the pipe rams of the lower row is displaced relative to the hole formed by the pipe rams of the upper row, which ensures sequential crimping of the pipe rams, the device is equipped with two sealed support pipes, and the holes formed during closing pipe rams of the lower and upper rows are located opposite the support pipes with the possibility of their tight coverage, and from below the support pipes are plugged and passed through the axial channel of the preventer, and couplings are screwed onto the upper end of the support pipes, allowing the support pipes to be sequentially suspended on the elevator, the packer is made removable with hydraulic landing, while the pump is hydraulically tied to the annulus of the well, while for installation and dismantling of the device using a lifting structure with slings.

Images